Non-dispersive solvent extraction of p-toluic acid from purified terephthalic acid plant wastewater with p-xylene as extractant

Content Provider	Semantic Scholar
Author	Kong, Qingran Cheng, Youwei Wang, Lijun
Copyright Year	2016
Abstract	Non-dispersive solvent extraction (NDSE) with p-xylene as extractant was employed as a novel separation method to recover both p-toluic (PT) acid and water from purified terephthalic acid (PTA) wastewater. The mass transport behavior of PT acid from aqueous solution to p-xylene was investigated by experiments and numerical simulation. Experiments showed that NDSE is feasible and effective. Residual PT acid in the raffinate can be reduced to lower than the permitted limit of wastewater re-use (100 g/m3) with extraction time longer than 60 s in industrial conditions. A mathematical model of PT acid mass transport was developed to optimize the membrane module performance. The model was validated with the experimental results with relative errors of less than 6%. Numerical analysis for mass transfer through the lumen side, the porous membrane layer, and the shell side showed that PT acid transport in the aqueous solution is the rate determining step. The effects of the membrane and operating parameters on membrane module performance were investigated by means of computational simulations. The key parameters suggested for industrial NDSE design are: fiber inner radius r1=200–250 µm, extraction time te=50–60 s, aqueous/organic volumetric ratio a/o=9.0, and temperature T=318 K.摘要目的采用对二甲苯为萃取剂, 通过非分散相溶剂萃取(膜基萃取)同时回收利用精对苯二甲酸(PTA)工业废水中的对甲基苯甲酸和水。创新点1. 采用非分散相溶剂萃取有效地实现了工业条件下PTA 废水的净化和资源的回收利用; 2. 采用数学模拟优化工业萃取的操作参数。方法1. 进行对二甲苯萃取实验, 考察操作条件对萃取效率和萃余水杂质浓度的影响; 2. 通过数学模拟, 建立膜萃取过程的数学模型, 对操作参数与膜结构参数进行敏感性分析。结论1. 非分散相溶剂萃取可以有效解决PTA 工业废水的回收利用问题; 2. 质量传递的速率控制步骤是管程中的水相扩散; 3. 优化的工业操作条件为:中空纤维膜内径为200∼250 µm, 萃取时间为50∼60 s, 水油两相体积比为9.0, 萃取温度为318 K。
Starting Page	828
Ending Page	840
Page Count	13
File Format	PDF HTM / HTML
DOI	10.1631/jzus.A1500281
Volume Number	17
Alternate Webpage(s)	https://rd.springer.com/content/pdf/10.1631%2Fjzus.A1500281.pdf
Language	English
Access Restriction	Open
Content Type	Text
Resource Type	Article